Crucible melting furnace



July z8, i925. 1,547,872

' l C. E. HAWKE CRUCIBLE MELTING FURNACE Filed March 25 1925 l-aten'tedJuly 28, 1'925.

UNITED STATES" CLARENCE E. HAWKE, E METUCHEN. NEW JERSEY, AssIGNoE 'roTHE CARBORUN- DUM COMPANY, or YANIA.

, 1,547,872 vearl-:rrr "orrice.-

NIAGARA FALLS, NEW YORK, A CORPORATION 0F PENNSYL- Application filedMarch-2.5, 1925. Serial No. 18,154.

To all 20110771.62? may cancelar: y Be it knownlthat I, CLARENCE E.II.\wKE, a 'citizen of the United States. residing at Metuchen, in thecounty of Middlesex and State of New Jersey, have invented a new anduseful Improvement in Crucible Melting Furnaces, of which the followingis a full, Clear, and exact description. g The presentinvention relatesto furnaces for melting metal, and more particularly ,to Cruciblemelting furnaces. 'lhe object of the invention is to provide aneliicient furnace of the latter type wherein the principle" of radiationfor heating the Crucible is employed and wherein direct flameimpingement on the Crucible is prevented. A preferred embodiment oftheinvention is shown in the accompanying drawings wherein. A

Figure l is a Central vertical section ofla Crucible melting furnace,the section being taken on the line I-I of Figure 2,l and Figures 2, 3.and`4 are sectional plan views of the furnace, the sections beingrespective'ly taken onk the lines III- III and IV-IV of Figure 1.'

The furnace shown in the illustrated lemv bodiment of thel inventioncomprises an outer shell 2 of steel having-a lining 3 of refractory andheat insulating material, such'as fire Clay. lVithin this outer liningis placed a system of horizontal circular flues 4, 5 and 6 the walls ofwhich are constructfed of lhighly refractory material capable ofradiating heat freely. I prefer to use for v .this purpose siliconcarbide refractory material.' The tlues are separated from each other byhorizontal partitions 7 and'S.' A port 9 extends through the wall of thefurnace for the admission of the burning' gases into the upper flue 4, aburner 10 being arv plate as this material is highly refractory lrangedopposite this port. It will be seen that the partition 7 vconstitutes aplate uponl which the burning gases impinge upon entering the flue 4.Silicon carbide is particuand has high mechanical strength.

A vertical partition 11 in the flue 4 adjacent the admission port 9compels the burning gases to travel in one direction through said flue,as indicated by the arrows in Figure 2, until they reach a port 12 inthe partition 7 adjacent the partition 11. This port departing admitsthe gases to the line 5, through which they travel in oppositedirections, as indicated by the arrows in Figure 3, until they reach apo1t`13 in the'partition 8. 'The port '13 admits the gases to fthe flue6 through which theytravel in opposite directions, as indicated by thearrows in Figure 4. The gases pass from the fluev 6 through ports 14into the inner chamber 15 0f the furnace, in which is located the cru-Cible or melting pot 16.

The gases, by the time they reach the inner Chamber 15 of the furnace,have been Completely burned and thus flame impingement on the Crucibleitself is prevented. These hot gases, however, passup through vthe spacebetween the Crucible and thefradiating surface of the combustion flueConstruction and are discharged at the top lthrough suitable openingsaround the top of the Crucible, vone of said openines being shown inFigure 1 .and designated by the reference numeral 17.

The furnace is provided with trunnions 18 whereby it is adapted to bemounted to tilt for the discharge of the metal melted within theCrucible so that the pot or Cru- Cible is not taken from the furnace,said pot or Crucible being firmly built into place within the heatingChamber of the furnace.

It will be seen that I have provided a. Crucible melting furnace whereinthe Crucible is heated both by radiation and by direct .Contactl of the.hot gases therewith.

completely burned before they come into Contact with the Crucible. Flameimp'ingement on the Crucible is thus prevented whereby the Alife of theCrucible is increased an appreciable amount. This method of heating alsoeffects a better utilization of lthe heat of the fuel employed and amore uniform heat-ing of the Crucible.

lVhile I have shown and described a pre- AThe flue construction compelsthe burning ferred embodiment of my invention, it will be understoodthat the invention is not limited to' its illustrated embodiment butthat it may be otherwise embodied wi-thin the scope of the appendedClaims without from the spirit lof the invention. I claim:

1.*A crucible melting refractory lining, a flue system within saidllining, certain of the walls of which are formed of refractory materialadapted tol radiate heat freely and which constitute the side Walls of achamber for receiving `the Crucible, and a Crucible within said chamber,said flue system communicating with said chamber adjacent its`lower endVand having 'an admission port for burning gases adjacent the upper endof said chamber, substantially as described. i

2. A cruciblemelting furnace having a refractory lining, a flue systemwithinfsaid lining, certain of the walls of whichv are formed ofrefractory material adapted to -V`radiateheatg freely and whichconstitute the "side walls vof a chamber for` receiving theCrucibleand'a Crucible within said chamber, said flue systemcommunicating with said chamber adjacent its lower end and having anadmission port for burning "gases adjacent the flue system comprising aplurality of intercommunicating flues each extending substantiallycompletely around said chamber, whereby the gases are compelled totravel a plurality of times about said chamber before being admittedthereto, substantially' as' described.

3. A Crucible melting furnace' having a refractory lining, a flue systemwithin said lining, certain of the Walls of lwhich are formedofrefractory material adapted to radiate heat freely and which constitutethe side walls of a chamber for receivin the Crucible, and a Crucibleheld within said chamber, said flue system communi ting with saidchamber adjacentdits low end v,and having an admission port for burninggases adjacent the upper end of. said chamber, said furnace having meanswhereby it is adapted to be mounted "to tilt for the discharge of theAmetal melted within the Crucible, substantially as described. c

4.1A Crucible melting furnace having a refractory lining, a l I saidlining, Certain of,` the vWalls of furnace having a upper end of saidchamber, saidy Y substantially as described.

flue system within which constitute side wallsI of a chamber for.receiving the Crucible, and a Crucible within said Chamber, said iuesystem communicating with saidl chamber adjacent 'its lower end andhaving an admission port for burn ing gases adjacent the upper end ofsaid chamber, substantially as described.l

5. A Crucible melting furnace havingl a refractory lining,.a siliconcarbide flue system Within said lining, Certain of the walls I of whichconstitute ysidewalls ofa Chamber for receiving., the Crucible, and aCrucible within said chamber, said iue system Comprising a plurality ofsuperposed intercommunicating horizontal tlues each extendingsubstantially Completely around said chamber, the upper iue havingv anadmission port for lburning gases and the lower Hue communicating withSaid chamberzat the lower end thereof, whereby the7 gases are Compelledto travel a plurality of times about said chamberbefore being admittedthereto,

y 6. A Crucible melting furnace, a cylindrical outer-metal shellhavingtrunnions whereby the furnace is ladapted to be mounted tocomprising` tilt for the discharge of the metalqmelted within` theCrucible, a refractory lining within .said shell, a silicon carbide fluesystem within said lining, certain of the Walls of which constitute theside walls of a chamber for receiving the Crucible,-

and a Crucible fixed within said chamber, said flue system comprising aplurality of superposed intercommunicating horizontal circular flueseach extending substantially completely around said Chamber, the upperiiue having an admission port for burning gases and the lower fluecommunicating with l v said chamber at the lower end thereof,

whereby the gases are compelled to travel a plurality of timesabout*said chamber 'bei fore being admitted. thereto, substantially asdescribed. r f

In testimony whereofI have hereunto set my hand.`lv i CLARENCE HAVVKE

